The invention relates to a method for electronically analyzing a time-variant signal having at least one extreme value, the amplitude and time of which are to be detected, by means of a detection circuit that operates as a peak value store and follows the time-variant signal after a threshold value is exceeded until the maximum amplitude is reached, wherein exceedance of the extreme value results in a peak indicator signal being generated and the maximum amplitude being stored.
In principle, a similar method is known from DD 248 893 A1. However, this document has no provision for taking into consideration a threshold value during the analysis. In this respect, this previously known method cannot be used to exclude noise and interference signals or peaks below a desired sensitivity threshold from the measurement from the outset. The signal tracker arrangement follows the input signal up to the maximum value thereof. Encountering of local maxima having a lower amplitude has no effect during the tracking. However, it follows every further rise in the signal to the highest maximum.
To capture not only the absolute value of the maximum but also the time at which it occurs, a peak indicator signal is generated whenever the rising signal is followed by a signal drop, which means encountering of a local maximum. This may be a square wave pulse, for example.
Comparison with a threshold value achieves the effect that the tracker mechanism is not activated until the threshold value is exceeded. Therefore, noise peaks and interference signals below the threshold value are not detected. The method presupposed to be known fails, however, if more than one extreme value is intended to be determined locally and with precise timing in the measurement cycle, since—as explained above—only the extreme value having the highest amplitude is ascertained in the previously known method.